Fig 5 - uploaded by Simon Potier
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Visual field of Harris's hawks and black kites with the eye at rest. Two views of the visual field of Harris's hawks (N=6; A,C) and black kites (N=3; B,D). (A,B) Orthographic projection of the boundaries of the retinal fields of the two eyes. A latitude and longitude coordinate system was used with the equator aligned vertically in the median sagittal plane. The bird's head is imagined to be at the centre of the globe (grid is at 20 deg intervals in latitude and 10 deg in longitude). (C,D) Horizontal sections trough the horizontal plane (90-270 deg) showing the visual field configuration of each species. Each chart represents the average retinal visual field when the eyes were at rest. 

Visual field of Harris's hawks and black kites with the eye at rest. Two views of the visual field of Harris's hawks (N=6; A,C) and black kites (N=3; B,D). (A,B) Orthographic projection of the boundaries of the retinal fields of the two eyes. A latitude and longitude coordinate system was used with the equator aligned vertically in the median sagittal plane. The bird's head is imagined to be at the centre of the globe (grid is at 20 deg intervals in latitude and 10 deg in longitude). (C,D) Horizontal sections trough the horizontal plane (90-270 deg) showing the visual field configuration of each species. Each chart represents the average retinal visual field when the eyes were at rest. 

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Thesis
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Animals evolve constrained by their surrounding environment, which shapes their responses to external inputs indirectly by selecting those behaviours that benefit to fitness. In one sentence, animals interact with their environment, and the ability of interfacing with the environment is mainly dependent upon their sensory capacities. These are some...

Citations

... However, it has also shown large knowledge gaps, some of which could potentially be filled by behavioural experiments, specifically using captive, tame and trained birds in falconries (e.g. [122]), and non-invasive techniques such as OCT ( Fig. 5; [46,59,123]), imaging with adaptive optics, and ultrasound. ...
Article
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... It is well accepted that flicker of artificial lights used in their enclosures can be detected by captive birds (Greenwood et al., 2004) and may affect their behaviour, such as mate choice (Evans et al., 2006), induce physiological stress (Maddocks et al., 2001;Evans et al., 2012) and potentially have an impact on visual performance, as shown in mice (Yu et al., 2011). In many countries, raptors are kept for purposes such as falconry or display, which can be essential for raptor conservation and research (Kenward, 2009;Potier, 2016). While most raptors are kept in outdoor aviaries, indoor aviaries using artificial lighting are also used for reproduction (Nelson, 1972). ...
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Birds, and especially raptors, are highly visual animals. Some of them have the highest spatial resolving power known in the animal kingdom, allowing prey detection at distance. While many raptors visually track fast-moving and manoeuvrable prey, requiring high temporal resolution, this aspect of their visual system has never been studied before. In this study, we estimated how fast raptors can see, by measuring the flicker fusion frequency of three species with different lifestyles. We found that flicker fusion frequency differed among species, being at least 129 Hz in the peregrine falcon Falco peregrinus, 102 Hz in the saker falcon Falco cherrug and 81 Hz in the Harris's hawk Parabuteo unicinctus We suggest a potential link between fast vision and hunting strategy, with high temporal resolution in the fast-flying falcons that chase fast-moving, manoeuvrable prey and a lower resolution in the Harris's hawk, which flies more slowly and targets slower prey.
Conference Paper
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